Aerosols are gaseous suspensions of fine solid or liquid particles. Aerosols are useful in a wide variety of applications. For example, medicated liquids may be administered in aerosol form. Medicated aerosols include materials that are useful in the treatment of respiratory ailments. In such applications, the aerosols may be produced by an aerosol generator and inhaled into a patient's lungs.
Aerosol generators are known that include a heated tube for vaporizing liquid. For example, commonly assigned U.S. Pat. No. 5,743,251, which is incorporated herein by reference in its entirety, discloses an aerosol generator including a tube and a heater operable to heat the tube to a sufficient temperature to volatilize liquid in the tube. It is disclosed that the volatilized material expands out of an end of the tube and admixes with ambient air, thereby forming an aerosol.
Other aerosol generators including a heated tube for vaporizing liquids to produce an aerosol are described in commonly-assigned U.S. Pat. Nos. 6,234,167 and 6,568,390 and U.S. patent application Ser. No. 10/003,437 filed Dec. 6, 2001 and U.S. Provisional Application No. 60/408,894, filed Sep. 6, 2002, each being incorporated herein by reference in its entirety.